• Structural Engineering and Mechanics
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• 제3권2호
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• pp.121-133
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• 1995

It is well known that two-dimensional simplified third-order theories satisfy the layer interface continuity of transverse shear strains, thus these theories violate the continuity of transverse shear stresses when two consecutive layers differ either in fibre orientation or material. The third-order theories considered herein involve four/or five dependent unknowns in the displacement field and satisfy the condition of vanishing of transverse shear stresses at the bounding planes of the plate. The objective of this investigation is to examine (i) the flexural response prediction accuracy of these third-order theories compared to exact elasticity solution (ii) the effect of layer interface continuity conditions on the flexural response. To investigate the effect of layer interface continuity conditions, three-dimensional elasticity solutions are developed by enforcing the continuity of different combinations of transverse stresses and/or strains at the layer interfaces. Three dimensional twenty node solid finite element (having three translational displacements as degrees of freedom) without the imposition of any of the conditions on the transverse stresses and strains is also employed for the flexural analysis of the laminated plates for the purposes of comparison with the above theories. These shear deformation theories and elasticity approaches in terms of accuracy, adequacy and applicability are examined through extensive numerical examples.

• 복합신소재구조학회 논문집
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• 제3권4호
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• pp.17-26
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• 2012

This study presents a governing equations of bending behavior of anisotropic sandwich plates with multi-layered laminated composite faces. Based on zig-zag models for through thickness deformations, the shear deformation of composite faces is included. All edges of plate are assumed to be simply supported. Results of the bending analysis under lateral loads are presented for the influence of various lay up sequences of antisymmetric angle-ply laminated faces. The accuracy of the approach is ascertained by comparing solutions from the sandwich plates theory with composite faces to the laminated plates theory. Since the present analysis considers the bending stiffness of the core and also the transverse shear deformations of the laminated faces, the proposed method showed higher than that calculated according to the general laminated plates theory. The information presented might be useful to design sandwich plates structure with polymer matrix composite faces.

• 한국강구조학회 논문집
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• 제12권6호
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• pp.749-758
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• 2000

본 연구는 지그재그모델에 근거하여 두꺼운 금속, 폴리머 복합재료 면재의 전단변형 효과를 고려해서 샌드위치평판의 휨해석 지배방정식을 유도하였으며, 판의 네 변은 단순지지 되어 있다고 가정하였다. 역대칭 적층면재의 화이버 각도와 면재의 적층수를 변화시켜가며 휨해석의 결과를 나타내었다. 해석방법의 정확성을 위해 일반 적층판이론의 값과 비교를 하여 검증을 하였다. 그 결과 적층판이론으로 구한 값보다 처짐에 있어서 더 큰 값을 나타냄을 알 수 있었는데, 그 이유로는 본 해석방법이 면재, 심재 모두 휨강성과 전단변형을 고려하였기 때문이라 사료된다. 강재, 폴리머 복합면재를 갖는 샌드위치평판을 설계할 때 제시된 정보를 유용하게 이용될 수 있을 것이다.